Newry and Armagh MLA Mr Bradley said he wanted to know who signed off the outline business case for the project and asked: "Was it Nelson McCausland, who was Culture Minister at the time?"

Mr McCausland said the committee had been told it was signed off by an official of the Department of Culture, Arts and Leisure (DCAL), and the committee clerk agreed to check.

Mr Bradley said: "If it is the case that it was signed off by you, you'd be in a very precarious position. It would be totally bizarre."

The comment came as a former senior civil servant warned the body set up to oversee safety at Northern Ireland's main sports stadiums was "somewhat" unprofessional and inconsistent.

Noel Molloy, who was DCAL programme director of the stadiums for the three key sports of football, rugby and GAA, told the committee of concerns over the work of safety technical group (STG).

In an evidence session Mr Molloy said he was "quite surprised" that STG chairman Paul Scott claimed he had been put under "undue pressure" by Government officials to approve plans for the revamp of Casement Park.

Mr Molloy, who is now at the McAvoy Group, said there were some STG concerns in relation to the Ravenhill rugby stadium, Windsor Park football ground as well as Casement Park.

He said "they didn't keep any minutes" and there was a feeling that "in relation to the STG's work at Casement Park that it was not as consistent with the previous work that had gone ahead with Ravenhill and Windsor".

Paraic Duffy of the GAA told the committee the organisation had "an exemplary safety record".

"I am here today to express our dismay at, and categorically reject any assertion that our supporters would ever be put at risk at any of our games, or within any of our stadia," he said.